Compressor



Aug. 8, 1939.` c. w. ALBERTsoN COMPRESSOR 2 Sheets-Sheet l Filed DeC. 19, 1936 2 Sheets-Sheet 2 11g- 8, 1939 c. W. ALBERTSON COMPRESSOR Filed Dec. 19, 1936 Patented Aug. 8, 1939,

UNITED STATES PATENT orrlcs This invention relates to compressors. and particularly to rotary compressors used for refrigeration.

'I'he principal object of the invention is to proy vide an improved compressor in which gas under head pressure is admitted to both sides of the compressor immediately after the compressor stops, so that the same may start again under substantially no-load conditions.

Other objects, advantages and capabilities of the invention will appear from the, following de -l scription of a preferredI embodiment thereof, taken in conjunction with the accompanying drawings, in which: ll Figure 1 is a longitudinal section througha compressor em my invention and ciated partsof a refrigerating machine;

Fig. 2 is an end elevation ofthe compressor, f the discharge pressure casing being removed:

- Fig. 3 is a sectional elevation-taken through the compressoren theline 2-3 of Fig. 1: Fig. 4 is a sectional plan .view through the compressor, taken on the line l-I of Fig. 2, and

Fig. 5 is a sectional detail view, taken on the line 5-5 of Fig. 2.

Referring to the drawings, the invention is ilof the condenser-compressor unit describedand claimed in my 'copending application Serial No.

' 30 68,188 med March 11, 1936. This compressor comprises two end plates I0 and Il and an intermediate plate l2 secured therebetween. A cylinder i3 is formed in the intermediate plate I2 and the end plates I 0 and II provide bearings il" and I5 in alignment therewith. A vshaft `Ii i isrotatably' mounted in said bearings and this shaft has an enlarged' eccentric member I1 located within the cylinder I3. Upon the eccentric member is mounted an impeller ring Il which has rigidly secured thereto a radiall` vane Il which is adapted to'siide between blocks 2l located in a cylindrical opening 2| in the plate' I2.

. I-'he outer end of the vane la is-infree communication with an opening 2 2 in the plate 'l2, which opening communicates through an open@ ing 23 in the plate l0 to the lower portion of the The chamber discharge pressure chamber 24. 24 is mounted yon the plate Il so as to encl the plateslll and I2.

'I'he shaft I6 extends through the plate I I, the

portion therebeyond being reduced as shown at 25 and being attached to a coupling-member 26 @whereby it may be flexibly coupled to the shaft 21 of an electric-motor. The plate Il is provided with'a boss which provides anfannular chamber 2l for the reception of. a counterbalance weight 29 rigidly secured on the shaft I6.' The chamber 28 is closed by an outer plate. 59. A metal bellows I0 is secured to the coupling member 26 and to an annular member 3| which has' a re- 5 duced annular-bearing portion abutting against the plate I9. The annular member 3|' is forcibly pressed against the plate 59 by. a spring 32 which also abuts against the coupling member 28. f

The bearing Il inthe end plate I0 isclosed '10 byl a plug $2 which is in Vspaced relationto the adjacent end of the shaft I6 so-as toprovide a lubricant chamber Il. The shaft II' has an vaxial bore 8l and a communicating .radial opening '36 .which communication between the l# chamber 3 4 and the chamber .28 and the metal bellows 2l. The chamber communicates withl the suction side of the chamber -I3 by means of .a'port Il. -This port-*is arranged so that it is!l .opened Vand closed by the 'annular impeller I8 20 during each revolution of-the shaft. Il. a

` The-radial vane I isv provided withgalo'ngitudinal duct 3l which is in li'ree communication with the opening 22 and through that opening with the lower .portion of the discharge pressure 25 chamber. The upper e'nd of the duct 31 comlustrated therein as applied to the compressor municates through a metering Opening 38 tothe. interior yofthe annular imbeller ilwhich has a longitudinal. groove 2l milled in it at that location.

. Y so The discharge duct 4l vin the plate Il ron' the .high pressure side of theV cylinder I ,l oommunicates with a valve chamber." on the outside of;4 f the platel Il. yThis housing contains a reed valve .42 adapted toclose the du`ct 40 and an overhang- 35.

ing iinger which prevents excessive displace` -ment of the valve from the plate M A discharge pipe 43 'extends from the valve chamber?" "and 'is preferably formed in ,its lower portion into oneor more covolutions to establish heat ex- 40 4change between the" hot compressed gases and the oil 'supply in the iowerxpart of the discharge pressure chamber 2G. The pipexllterminates in an open end in the upper portion 'of the diseharge pressure chamber 2|. Any oli entrained 45 -wun themes fauslnto une lower part ofthe vdischargepressura chamber 2l. A A gas lead oi! pipe M is connected to the upper end of the dis- .charge pressure chamber 24. The pipe Il supvplies gas to condenser coils '(not.shown)' which w supply condensed lrefrigerant to va lreceiver (not shown) from, wiieh theuquened refrigerant is supplied tothe evaporator (not shown) of therefrigeration system as needed.-

The vaporized refrigerant isreturned to the u "ment around the'cylinder I3.

suction side. oi.' the cylinder by means of a pipe 46 which communicates with an intake port 41 which is coveredand uncovered by the annular impeller Il during each revolution oi the shaft located in the upper part of the discharge pressure chamber 24. The capillary tube 49 may suitably have an internal diameter of twenty-ve one 'thonsandths of an inch (0.0025 inch) and a length of about twelve inches. These dimensions are given by way of example only, since they may be varied considerably as long as'the capillary serves as a high resistance liquid seal which is maintained during normal operation of the compressor and which blows out' when the compressor stops, admitting gas under head pressure into the compressor chambers and into the 'intake pipe 46 so as to apply strong closing pressure on the check valve 48.

- Th'e operation is as Yollows: The operation of the motor causes the eccentric member I1 to rotate in counter-clockwise direction, as viewed in Fig. 3. The impeller member I8 is caused to Iexecute a combined oscillatory 'and orbital move- The clearances are such that the gas pumping depends upon lubricant sealing and high speedoperation, f or example, around tvvo thousand revolutions per minute. At each revolution oil is fed through the duct 31 to the compressor. VA part oi the oil passes 'between the shaft I6 and bearing I4 into the chamber 34 from which it passes through the ducts 35, 36 into the annular chamber 28.

A part zof the oil 'passes through the bearing L` intothe chamber 28. 'The 'oil passes from the chamber 28 back into the cylinder I3by duct 35. The oil in the cylinder I3 maintains a peripheral seal between the cylinder I3 and the annular impeller I 8' and a certainamount of lubricant is expelled with the compressed gases backinto the discharge pressure 'chamber 24 at each revolution. At each revolution a small plug of oil is forced into thel capillary 49 and under normal operating conditions the capillary 49is maintained substantiallyfull of lubricant, the head pressure .within the' discharge pressure chamber 24 being unable to overcome the viscosity of the lubricant and blow it back into the cylinder I3 When the motor is stopped the oil inv thecap'il-4 lary tube 49 is no' longer renewed and the gas under high pressure in the discharge pressure 'chamber 24 blows the oil therein into 'the cylinder I3. :The high pressure gas passes readily into "i the cylinder I3 and displaces the oil ilm on the`\ annular impeller Il so that the gas passes freely` to the suction side of the'compressor. The result is that the compressor is substantially unloaded and is able to start operation again very readily. Furthermore, when the motorstops, the head pressure is applied to the check valve 4B so. as

`positively to close that. valve.

Although the invention has been described in connection ywith the speciiicdetails of a preferred embodiment thereof, it must be understood that such details are not intended to be limitative of the invention except'in so far as set forth in the accompanying claims.

I claim:

1. In combination, a gas compressor, 'a chamber enclosing said compressor, into 'which the compressor delivers, means for maintaining a supply of lubricant' within the compressor, a Valve in the outlet 'of said compressor, and open kmeans establishing a high resistance liquid seal between said chamber and a low point of said compressor which is subjected regularly to compression.

2. In combination, a gas compressor having a suction inlet and a pressure outlet, a chamber enclosing said compressor, into which the outlet delivers, means for maintaining a supply of lubricant Within the compressor, a check valve in said outlet, and an open capillary tube having a high liquid resistance communicating with said chamber and with a-low point on the pressure side of the compressor and adapted to be sup- .plied withl successive slugs of lubricant during tain sealing relation between relativelymoving parts inl high speed operation, and a relatively long open restricted duct extending'between the chamber and compressor, saidlduct being arranged to be supplied with sealing iiuid during operation of the compressor, the liquid of the seal being blown out when the compressor stops to admit gas under pressure to the compressor and inlet pipe to unload the compressorand positively to close the check valve.

4. In combination, a gas compressor comprising a cylinder, a gyratory impeller'having an 'or bitalmovement therein, a vane cooperating with the impeller separating the suction and pressure sides ofsaid compressor, an inlet pipe communi- 'catingwith the suction/side of' the compressor, a check valve in said inlet pipe, a discharge duct on the pressure side of the compressor, a discharge pressure chamber into which the. duct discharges, a check valve in said' duct, means for maintaining a supply of lubricant in said cylinder to maintain sealingfv relation between relatively moving parts in high speed operation, and a relatively long capillary tube communieating with the discharge pressure chamber and the pressure. side of said compressor adapted to receive a slug of lubricant during each revolution of the compressor to maintain a high resistance liquid seal during high speed operation, the/capillary tube being open whereby the liquid seal is blown out when the compressor stops to admit gas under pressure tofthe compressor and inlet pipe to unload the compressor and positively to close the check valve. y

CARL W. ALBERTSON.v 

